JP2003042802A - Marked disc for angle-of-rotation sensor, angle sensor for rotary part and reference value determination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve a marked disc so that the economical production is ena bled, a size and mass can be reduced maximully and the stability under vibra tion load and the maximum allowable number of rotations are sharply improved. SOLUTION: The marked disc 11 for an angle-of-rotation sensor for a rotating part is equipped with a large number of angle marks 12, which are turned in a radial direction especially with respect to a rotary axial line to be provided in a form of a rim concentrically arranged especially with respect to the rotary axial line, and at least one reference mark 12a. A reference mark is formed by the angle marks different in modulation characteristics and unified with the rim of the angle marks.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a number of angular marks, which are provided in the form of a rim which is particularly radially oriented with respect to the axis of rotation and which is arranged concentrically with respect to the axis of rotation, at least. A rotating disk, in particular a marked disc for a rotation angle sensor for the rotation axis, with one reference mark, and more particularly a radial orientation with respect to the rotation axis, in particular with respect to the rotation axis Marked circle connectable to a rotating part, having a number of angle marks in the form of concentrically arranged rims, at least one reference mark and a fixed scanning unit for the angle marks A rotating part comprising a plate, at least one transmitter of electromagnetic radiation, a receiver for the radiation modulated by the marked disc, and a connection means to the evaluation unit, A rotation angle sensor for the rotation axis, and further an analog signal is obtained by modulation of the transmitted signal by a number of marked discs and at least one reflective mark whose modulation quality is different from the marked discs, It relates to a method for determining a reference signal from an analog signal, in which the processed signal is received by a receiver, fed to an evaluation unit and, if necessary, further digitized.

[0002]

BACKGROUND OF THE INVENTION It is necessary in many areas of technology to determine and display the current angular position of rotating parts in real time, i.e. ignoring small signal delays.
For example, in research and development of internal combustion engines and in mass production applications of internal combustion engines, angle sensors for the current rotational position of the crankshaft or camshaft are used. In this case, various measuring principles are used.

A particularly advantageous system uses a disc with angle marks which can be mechanically connected to a rotating component and a sensor device for scanning the angle marks provided on the disc. The angle mark is arranged radially with respect to the axis of rotation and preferably concentrically with respect to the axis of rotation. In this case, two measuring channels are provided. With this measuring channel, two rows of angle marks are scanned separately from each other by the two sensor systems. That is, an incremental track having a large number of equally spaced angle marks, for example 720 angle marks per revolution, and a reference track having, for example, one reference mark per revolution, are scanned separately. The rotational angular position of the disc, and thus of the rotary component, can be determined from the angular mark signal of the incremental track and with reference to the reference mark. This fiducial mark can indicate, for example, the position of the top dead center of the cylinder of the piston machine. The sensor device is preferably an electro-optical system which scans the angle mark by transmitted or reflected light and, optionally after digitization, supplies it to a display device and / or an evaluation device. The shape of the angle mark and the sensitivity characteristics of the sensor are then matched to one another, and preferably also the radiation emission of the transmitter. In this case, a generally elongated slit-shaped light-transmitting window and light-receiving window are directed at the dashed angle marks, both radially and substantially parallel to the axis of rotation. To prepare the sensor signal, analog electronics are provided with the smallest possible time lag. In this case, a high-speed comparator derives a digital trigger signal from the amplified analog signal of the angle mark sensor. This trigger signal indicates the time when the respective rotational angular position is reached. Digital signal processors have not heretofore been proved to be effective on the basis of the time calculation and the unavoidable time shifts involved. On the other hand, the above system, in particular, makes it possible for the user to determine the absolute angular position of rotating parts in
Guaranteed with high accuracy and angular resolution and with a negligible time lag between the given angular position of the part and the output of the associated signal.

However, the above system is
In the case of two optoelectronic measuring channels or in the case of several tracks, the optoelectronic measuring channels are expensive, space-consuming and have a considerable contribution to the weight and / or mass of the measuring device. The size and mass cause interference, especially in the case of high speed small engines. With this smaller engine, the additional (flywheel) mass of the crankshaft becomes noticeable. The size and mass also result in disturbing effects when the engine is already installed in a vehicle, in relation to the confined space or the large vibrational accelerations to which the measuring device is exposed during the actual operation of the engine.

Therefore, simple and inexpensive solutions have already been proposed. This solution has only one measurement channel,
Often has one inductive sensor. In the case of this sensor, the reference position is given by the deviation from the otherwise equidistant placement of the angle marks. For example, the teeth are read in the case of a toothed disc for indicating the reference position. The evaluation unit recognizes the missing tooth and indicates the arrival of the reference position by constantly measuring the rotational angular velocity or from the expected time of the subsequent rotational angular interval. By estimating from the time of the preceding rotation angle interval each time, the missing angle mark signal is simulated. This, however, has the important drawback that the accuracy of the preceding rotation angle measurement is greatly reduced. This is because both the reference position and the current rotation angular velocity can only be approximately indicated because the current rotation angle information is missing in the angle mark gap required for coding the reference position. . Moreover, the required calculations are not a little off-due. Therefore, such a system is inaccurate and can only be used conditionally, for example for the research and development of internal combustion engines, for the analysis of rotational inhomogeneities and rotational vibrations or for the detection of precise measurement data synchronized with the crank angle.

[0006]

Therefore, the object of the present invention is to be economically producible and to be able to reduce the size and mass to the maximum extent, whereby the stability under vibration load and the maximum permissible rotational speed are achieved. Is to improve the system or its components mentioned at the outset. In doing so, the accuracy of the angular resolution should be high and invariant over rotation, but the time offset should be negligibly small when determining information from at least two angular information channels.

[0007]

According to the invention, this object is to provide only one track of angle marks, one reference mark or each reference mark being formed by an angle mark with a different modulation characteristic. Is solved by a disc with a mark featuring. This means adding multivalued logic to the structure of the angle mark. This angle mark is suitable for scanning by the sensor and subsequent signal evaluation, making information from more than one angle information channel available from only one scanning sensor device. It also fulfills the requirements for measuring principles that are clear and real-time possible for the user. The additional information (eg information about the reference position) is contained in the same channel as the primary information, without depending on the primary information (eg the preceding angular position) and without requiring or creating a gap in the primary information. Be done.

On the other hand, in the case of an angle sensor arrangement having a plurality of measuring channels, not only one channel has multivalued logic according to the invention, but also two or more channels have multivalued logic. By having
A large number of information can be determined for an individual channel with minimal cost (large spacing between individual values of multivalued logic and thus easy distinction of this value).

If the reference mark has an area different from that of the angle mark, the modulation of the transmission signal can be easily achieved in both reflected light and transmitted light. In that case, the different areas and the values of the scanning signals produced thereby show different values of the multivalued logic. In this case, a number of the same values indicate the preceding angle mark, and at least one other value with a deviation serves as a reference mark. The general application of the principles according to the invention is not restricted to three-valued logic, but four-valued or higher-valued logic allows more information to be accommodated in one channel. This area coding is applicable not only to optical measurement methods which give rise to lightness coding (eg dark-bright-2x bright), but also for capacitive methods, for example. In principle, multivalued angular mark tracks can be realized for all kinds of scanning principles, ie capacitive, inductive, optical, acoustic or other measuring methods.

If the reference mark has a larger area than the angle mark, the evaluation is very simple. The threshold for recognizing the deviation of the reference mark from the angle mark can then be realized and determined very easily.

It is advantageous if the area coding is carried out in such a way that it does not reduce the angular resolution. In this case, according to another feature of the invention, the reference mark extends radially and / or circumferentially with respect to the angle mark. As a result, the widths of the broken lines (marks) in the circumferential direction that determine the angular resolution are the same, and the triggering of the reference signal is performed accurately at the same intervals as the intervals of conventional angle marks.

At this time, the radial extension of the reference mark is
It is advantageous to have a width that is shorter than the angle mark in the circumferential direction of the disc. This shape of the reference mark gives the same edge steepness as all other angle marks when starting the scan by the receiving window, so the signal extension shape of all marks is the same extension at the critical triggering point. Have a shape. In the case of "conventional" angle marks, only after the leading edge has reached a new stable signal value, an additional signal increase should be used for the extreme values with deviations, if the reference mark is specially characterized. Is. This is achieved by the gradual change in dashed line length described above.

Analogously to this, according to another embodiment of the invention, each angle mark is composed of at least two angle mark parts which are arranged radially and are spaced apart from each other, the angle mark parts being discs. The above effect can be achieved if the reference marks have substantially the same width in the circumferential direction and the radial extension of the reference mark is a section that connects both angle mark portions.

If the receiving window of the sensor is not oriented exactly parallel to the angle mark, or is oriented exactly parallel, for example due to mechanical disturbance factors or under-adjustment, the resulting error is The angle mark and / or the reference mark are minimized by being formed symmetrically in the radial direction. If the angle mark and / or the reference mark are formed symmetrically with respect to the direction of rotation, ie with respect to the dashed thickness center, the marked disc provides in both directions of rotation the same signal which is relatively insensitive to the orientation error of the receiving window. .

In another embodiment of the invention, the angle marks and / or fiducial marks are formed by the radiation-permeable areas of the marked disc. This is particularly advantageous for transmitted light systems in which the mark is formed by a notch in the disc that does not transmit light.

In another embodiment of the invention, the angle marks and fiducial marks are formed by reflecting surfaces on a marked disc. This is considered to be a variation of the measurement with reflected light.

For this type of measuring method, instead of an area coating, it is possible for the fiducial mark to have a reflection coding different from the angle mark, in particular a reflection coefficient different from the angle mark. The considerations that are relevant to the shape of area coding are then also applicable to reflection coding. That is, the reflection mark is formed by an angle mark having a strong reflection, for example, an angle mark integrating a region having a strong reflection. This makes it possible to completely avoid all errors caused by the area deviation between the angle mark and the reference mark.

The problem mentioned at the outset is also solved by an angle sensor. According to the invention, this angle sensor comprises a disc with marks provided with angle marks of only one track, one reference mark or each reference mark being formed by angle marks of different modulation characteristics. It is characterized in that only one light-transmitting window or one light-receiving window facing each other is provided. This means that multi-valued logic is realized by the structure of the angle mark. This logic makes it possible to obtain information by means of one scanning sensor device from more than one angle information channel by appropriately adapting the sensor scanning and the subsequent signal evaluation. Thereby, the number of scan channels can be reduced, in the best case to one scan sensor device. On the other hand, in the case of an angle sensor structure with multiple measuring channels, not only one channel has multi-valued logic according to the invention, but more than one channel can also have multi-valued logic. It is therefore possible to detect a large number of information at a low cost of the individual channels (large spacing between the individual values of the multivalued logic, with the consequent easy distinction of this value).

In order to enable triggering accurately and uniformly for all marks, the light-transmitting window or the light-receiving window has a narrower width in the circumferential direction of the marked disc than the angle marks.

In a first embodiment, each receiving window is provided on the side of the marked disc opposite the associated transmitting window. Thereby, a scanning sensor device of the translucent principle can be used.

In another embodiment of the invention, each receiving window is provided on the same side of the marked disc as the associated transmitting window. This has the advantage that the structure of the angle sensor device is further simplified. Thus, the conductors leading to the transmitter and receiver can be laid with the same protective sheath, avoiding or minimizing conductor splitting or increased mounting space for the transmitter and receiver.

This advantage, according to another feature of the invention,
The sending and receiving windows coincide, this common window having at least one exit point for the radiation directed towards the marked disc and at least one entrance point for the radiation reflected by the marked disc. Once equipped, it is maximally available. This combination of light-transmitting and light-receiving windows can be achieved, for example, by dividing the light-transmitting area and the light-receiving area into a large number of small points, preferably at the entrance or exit points of the individual optical fibers.

In order to solve the problem mentioned at the beginning of the above angle sensor, according to the present invention, for each angle mark and reference mark, this tendency of the extreme value continues from the analog extreme value of the preceding angle mark. A method is suitable which is characterized in that the extrema to be determined are modified and changed by a predetermined value and the modulation is used in the evaluation unit as a threshold indicating a different reference value. Angular position detection based on ordinary angle marks relies on proven methods such as those mentioned at the outset, i.e. producing a signal whose phase and amplitude follow the analog input signal and which is digitally detected at the signal edge by a high speed comparator. This is advantageously done by detecting the intersection of the angle information as a trigger point. This method applies to fiducial marks as well. A continuous analog according to the invention of the trigger voltage with respect to the reference position in order to reliably distinguish the reference mark from the rest of the angle mark, without depending on transient changes in the signal level or changes in the zero point of the sensor signal etc. Electronic tracking is performed.
In this case, the current average value of the sensor signal is determined and the trigger threshold is determined by adding or subtracting a set constant voltage or by multiplying a set coefficient. It is likewise possible to start from the extrema of the sensor signal by means of small constant addition or subtraction voltages or by adapted multiplication factors.

For each angle mark and reference mark,
From the analog brightness extreme value of the preceding angle mark, the extreme value corresponding to the tendency of this extreme value is determined, changed by a predetermined value, and used as a threshold value indicating a reference value with different brightness, The method is advantageous and extremely simple to use in terms of circuit technology.

In practicing the method, the modulation of the electromagnetic radiation of the transmitter takes place in the form of changes in the reflected or transmitted radiation by means of angle marks and reflection marks, according to the invention, an analog extremum of intensity is determined and To be evaluated.

[0026]

DETAILED DESCRIPTION OF THE INVENTION The present invention will now be described in detail with reference to the accompanying drawings showing a preferred embodiment of a crank angle sensor system according to the present invention. However, the invention is in no way limited to this embodiment.

Next, as a preferable application of the angle sensor according to the present invention, a crank angle sensor for an engine, which is used as a basis of the indicating technique, will be described in detail. The pressure in the combustion chamber is measured to indicate the internal combustion engine. In order to obtain a continuous pressure curve, the pressure values must be precisely assigned to the respective crankshaft position. The crankshaft angular velocity is not uniform due to the periodic irregularities. Therefore, each time-based data record is not a correct assignment for crank angle. The crank angle sensor is independent of the number of revolutions and allows the correct assignment to the current crank angle. Furthermore, it is necessary to show the top dead center correctly. Different angular resolutions are needed depending on different tasks (eg 1-0.1
°). Due to physical limitations, it is not possible to mount 3600 marks (0.1 ° resolution) on the limited circumference of the disc, so an electronic pulse multiplier is usually required. is there. A high resolution of 0.1 to 0.2 is required, for example, for injection point tests or engine knock detail tests. A resolution of 1 ° is sufficient for simple combustion chamber pressure measurements or IMEP calculations.
Normally, two positions are discussed for mounting the crank angle sensor on the engine. It is a drive train directly connected to the free end of the crankshaft or the engine. Mounting locations on camshafts or other flexible shafts should be avoided for combustion pressure measurements. This is because in the case of such an indirect measurement, a large error may occur between the crankshaft and the measurement position due to play (twist). Normal measurement accuracy is ± 0.1 ° in crank angle.

Mounting the angle mark on the free end of the shaft and the pressure sensor on the nearest cylinder is preferred for the best results. At this position, the crankshaft twist is minimal. Therefore, FIG. 1 shows a crank angle sensor system according to the invention fixed to the free end of the crankshaft. The sensor system comprises a flange joint 1, a closed casing 2 and a support arm 3 fixed to the casing 2. A marked disc rotates within the casing, the disc having 720 crank angle marks mounted on its surface and at least one fiducial mark provided therebetween. The support arm has a clamp device 4 for mounting on the engine block M. At this time, the support arm 3 and the clamp device 4 have a freedom of movement in a direction in which the support arm is perpendicular to the crank axis, and the support device 3 and the clamp device 4 are attached to the engine block M by the clamp device in the axial direction and the radial direction with respect to the crank shaft. It is formed so as to be supported. A typical angle sensor comprises two titanium shaft units mounted on deep groove ball bearings and the casing 2 is preferably made of high strength aluminum alloy. The support arm 3 is formed near the casing 2 as a thin, flat metal plate 5, i.e. in the form of a leaf spring. Therefore, the support arm 3 is elastically deformable from the plane of the metal plate 5, but
It has rigidity in the plane of the metal plate 5. Thereby, the casing 2 allows for the actually occurring movement of the crankshaft free end of the sawdust.

From the casing 2, a fiber optic cable 6 having a length of about 2 m is guided to the sensor electronics 7. The cable preferably consists of two separate fiberglass bundles, preferably protected from damage by metal tubes. The sensor electronics 7 comprises all the components for converting an optical signal into an analog signal (light / voltage conversion) and further into a digital signal. The signal transmission of the sensor electronics 7 is preferably very unobtrusive and allows the cable to be long LV.
It is performed by DS technology (low voltage difference signalization). The fiber optic conductor 6 is preferably detachable from the sensor electronics 7 and is guided to the circuit board via a plug connector. Furthermore, a connection cable 8 is guided from the sensor electronics 7 to the pulse transformer 9. In this case, the cable is preferably a bayonet, in particular about 5 m long, and can be connected in series. The pulse transformer 9 that synchronizes the received signal and converts it into a TTL signal may include a pulse multiplier for increasing the resolution. The pulse transformer can be directly connected to the indicating device via another connecting cable 10. If required, a separate energy supply unit can be provided. The electrical components are not in direct contact with the engine and are therefore mounted so that they are not exposed to mechanical effects (vibration) and are advantageously protected against thermal stress and electrical disturbances .

FIG. 2 shows a disc 11 with a mark and a sensor 13.
Shows that they are mounted separately from each other.
The marked disc 11 of the crankshaft sensor system, which is fixed to the shaft, for example via a clamping plate, is provided with angle marks as shown. This angle mark 12 is preferably formed as a number of marks in the form of a rim which are oriented radially with respect to the axis of rotation and are arranged concentrically with respect to the axis of rotation of the marked disc 11. In this case, of course, at least one fiducial mark must be provided for triggering. According to the invention, the marked disc 11 comprises an angular mark 12 of one track, the reference mark being formed by angular marks having different modulation characteristics, as will be described later. A sensor head 13 is provided facing the angle mark 12 of this track. This sensor head is preferably fixed to a thin metal plate 5. The sensor head 13 preferably comprises at least one window hole 14. The window hole itself is oriented parallel to the angle mark 12 by orienting the sensor head 13. One or two light guides forming at least one light-transmitting window and at least one light-receiving window may reach in each window hole.

The principle function of the angle sensor is based on a light source, in particular an infrared source, arranged in the sensor electronics 7, as shown schematically in FIGS. 5a and 5b. This light source supplies light having a constant intensity to the marked disc 11 via one optical fiber 15. The reflected light is the other optical fiber 1
You will be guided to the photocell via 6. This photocell is likewise provided in the sensor electronics 7. In the embodiment of FIG. 5a, the angle mark 12 is reflective and the rest of the disc is shaped to absorb light. In the case of the alternative embodiment shown in FIG. 5b, for example a perforated steel disc 11a is used. This perforated steel disc 11a is inserted between the sensor and the reflector. The light passes through the hole and the disk 11
Is blocked by the rest of the. When the marked disc 11 or 11a rotates, a sine-like optical signal S is generated by the photocell in the sensor electronics 7 and the associated electronics, as shown in FIG. 7b. This analog optical signal S is then converted by the sensor electronics 7 into a digital electrical signal D, as shown in Figure 7c.
Therefore, the amplitude of the received signal S is cut off by the switching threshold S '. The intersection of the two signals S and S ′ is the transition point of the digital signal D. This digital signal is square and is guided to the pulse transformer 9.

A typical pulse transformer 9 supplies 720 crank angle pulses and one trigger pulse. The negative (falling) edge of the signal is then preferably used to evaluate the crank angle signal. Depending on the required resolution and depending on the subsequent pointing system, a pulse multiplier (digital PLL type) is provided in the pulse transformer case 9. The resolution can be selected by the switch of the pulse transformer 9. In the unlikely event, the necessary multiplication circuit can also be integrated in the circuit of the pulse transformer 9. It is advantageous if the sensor units 1 to 7 can be easily separated from the pulse transformer 9. In the test cell, it is expedient for the time saving that the test engine is still running and the engine to be tested next is already prepared outside the cell by assembly of other sensor units.

The marked disc 11 used, for example, for the reflection method according to FIG. 5a consists of poly-carbon with a light-absorbing layer and a reflecting angle mark 12. In the case of state-of-the-art (a in FIG. 6) marked discs, the angle mark 1 as described in connection with FIGS.
The required fiducial mark 12a provided in the track separated from two can be integrated in the track of the angle mark 12 in the present invention. According to the present invention, the reference mark 12a is formed by the angle mark 12 having different modulation characteristics. Therefore, the reference mark 12a preferably has an area different from that of the angle mark 12, particularly a large area. To that end, the fiducial mark 12a extends radially relative to the angle mark 12 and, if necessary or instead, circumferentially, as shown in FIG. 7a. The radial extension has the advantage that the circumferential resolution at the reference mark 12a, ie the angular resolution, does not differ from the resolution of the conventional angle mark 12. In another embodiment of the marked disc 11, the marked disc is manufactured as a marked disc of laser-cut high-strength steel. In all cases, the outer diameter depends on the required maximum speed and the vibrations that occur.

The radial extension of the reference mark 12a has a width in the circumferential direction of the disc 11 which is narrower than that of the other angle marks 12, and by extension, the central section of the reference mark 12a. Therefore, as shown in FIG. 7b, the reference mark 12a
The beginning and end of the edge extension shape of the analog optical signal S in FIG. That is, for each mark 12 or 12a on the marked disc,
The same edge steepness occurs in the lower range of the analog optical signal S. This guarantees the same signal shape of the digital signal D (see FIG. 7c) for all the marks 12, 12a and thus a constant angular resolution over the entire circumference of the marked disc 11. The signal level of the analog optical signal S with respect to the reference mark 12a is shown in FIG. 7 according to the same lowest edge extension shape for all the angle marks 12, 12a.
, B, and finally exceeds the evaluation threshold value B. In this case, the intersection of the signal S and the evaluation threshold B determines the start and end of the digital reference signal R (d in FIG. 7).

FIG. 8 shows the angle mark 12 and the reference mark 1.
An alternative embodiment of 2a is shown by way of example. Each angle mark 12 'consists of at least two angular mark portions arranged radially and spaced from each other, the angle mark portions having approximately the same width in the circumferential direction of the disc. The radial extension of the fiducial mark consists of a section connecting both mark portions.

According to another embodiment not shown,
The difference between one or each fiducial mark 12a and the angle mark 12 can be produced by reflection coding instead of area coding as described above. In particular, it can be caused by a reflection coefficient of the reflection mark 12 a which is different from the angle mark 12 and preferably larger than the angle mark 12.

A very advantageous method for determining the evaluation threshold B of the reference signal, for example, will be described with reference to FIG.
From the analog signal S obtained by a large number of angle marks 12 and at least one reference mark 12a whose modulation quality is different from that of the angle marks 12, this determination due to signal drift, local contamination of the marked disc 11 etc. is reduced. Without this, the fiducial mark 12a should be reliably determinable. To that end, in the computing unit of the system for each angle mark 12 or reference mark 12a, from the analog extremum of the preceding angle mark 12 or reference mark 12a, the extremum that continues this extremal trend is determined and determined. Is used as a threshold B indicating a different reference value for the modulation. Therefore, the evaluation threshold B follows the tendency of the extreme value of the amplitude of the analog signal S. In this case, preferably,
The distance between the evaluation threshold B and the envelope curve of the extreme values of the signal S is
It can be changed in proportion to the magnitude of the extreme value, particularly in direct proportion. This method is advantageously evaluated because of the high processing speed of the analog extremum of the strength of the signal S and by this signal.

[Brief description of drawings]

FIG. 1 is a schematic view of a part of an angle sensor system mounted on an engine.

FIG. 2 is a schematic side view of a system in which a marked disc and a sensor are mounted separately from each other.

3 is a plan view and partial side view of the system of FIG.

FIG. 4 is an exploded view of the system of FIG.

FIG. 5 a is a diagram schematically showing an embodiment of an angle sensor and b is an alternative embodiment of the angle sensor.

6A is a diagram showing a disc with marks according to the state of the art, and FIG. 6B is a diagram showing a disc with marks according to the present invention.

FIG. 7a is a diagram showing one reference mark and some angle marks according to an embodiment of the present invention. b is a figure which shows the analog signal corresponding to an optical signal. c and d are diagrams showing the shapes of a digitalized electric angle signal and a trigger signal derived from an analog signal.

FIG. 8 is a diagram showing alternative shapes of an angle mark and an associated reference mark.

FIG. 9 is a diagram showing a principle of deriving a reference threshold value of a reference mark depending on a signal of an angle mark.

[Explanation of symbols]

11 Disc with mark 12,12 'Angle mark 12a, 12'a reference mark 14 Light receiving window

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Klaus Wrightmeier             Austria, Graz, Burgaga             Seth, 13 F term (reference) 2F065 AA39 AA40 BB06 BB16 BB27                       CC11 DD02 DD14 FF02 FF18                       FF23 HH15 JJ01 JJ09 JJ15                       LL02 LL12 LL19 LL29 PP13                       QQ25 QQ28                 2F077 AA38 NN02 NN23 NN28 NN30                       PP19 QQ11 TT32 TT35 VV01                 2F103 BA10 BA32 BA37 BA43 CA02                       DA01 DA13 EA02 EA12 EB01                       EB11 EB32 EC08 EC11 FA15

Claims (18)

[Claims] 1. A number of angle marks, which are oriented radially with respect to the axis of rotation and are provided in the form of rims which are arranged concentrically with respect to the axis of rotation and at least one reference mark. In a rotating disk with a rotating component, in particular with a marked disc for a rotation angle sensor for the axis of rotation, only one track of the angle mark (12) is provided, one reference mark or each reference mark (12a). ) Is formed by angle marks (12) having different modulation characteristics. 2. The reference mark (12a) is an angle mark (1).
The marked disc according to claim 1, having an area different from that of 2). 3. The reference mark (12a) is an angle mark (1).
The marked disc according to claim 2, which has a larger area than 2). 4. The reference mark (12a) is an angle mark (1).
The marked disc according to claim 3, which extends in a radial direction and / or a circumferential direction with respect to 2). 5. The radial extension of the reference mark (12a) is an angle mark (12) in the circumferential direction of the disc (11).
The marked disc according to claim 4, characterized in that it has a width shorter than that. 6. At least two angle marks (12 ') are arranged radially and are spaced apart from each other.
A section in which the angle mark portions have substantially the same width in the circumferential direction of the disc (11), and the radial extension of the reference mark (12'a) connects both angle mark portions. The disc with mark according to claim 4 or 5, characterized in that 7. An angle mark and / or a reference mark (1
The marked disc according to any one of claims 3 to 6, wherein (2, 12a, 12 ', 12'a) are formed symmetrically in the radial direction. 8. An angle mark and / or a reference mark (1
2, 12a) is formed by the radiation-permeable range of the marked disc (11).
A disk with a mark according to any one of to 7. 9. An angle mark and a reference mark (12, 1)
A marked disc according to any one of claims 1 to 8, characterized in that 2a) is formed by a reflective surface on the marked disc (11). 10. Marked disc according to claim 9, characterized in that the reference mark (12a) has a different reflection coding than the angle mark (12), in particular a reflection coefficient different from that of the angle mark (12). 11. A number of angle marks, which are oriented radially with respect to the axis of rotation and are provided in the form of rims which are arranged concentrically with respect to the axis of rotation and at least one reference mark. A marked disc connectable to a rotating part, with a fixed scanning unit for the angular mark, at least one transmitter of electromagnetic radiation, and a receiver for the radiation modulated by the marked disc. In a rotary angle sensor for a rotating component, in particular for a rotary axis, with a bar and a connecting means to the evaluation unit, the marked disc having an angle mark (12) for the track with only one, one Of the fiducial marks or each fiducial mark (12a) formed by angle marks (12) with different modulation characteristics and facing the track of the angle marks (12). An angle sensor characterized in that only one light-transmitting window or light-receiving window (14) is provided for each. 12. The angle sensor according to claim 11, wherein the light-transmitting window or the light-receiving window (14) has a width narrower than the angle mark (12) in the circumferential direction of the marked disc (11). 13. The light receiving window is a disc with a mark (1
13. An angle sensor according to claim 11 or 12, characterized in that it is provided on the side of 1) opposite the associated light transmission window. 14. Angle sensor according to claim 11, characterized in that each light-receiving window is provided on the same side of the marked disc (11) as the associated light-transmitting window. 15. A light transmitting window and a light receiving window (1
4) coincides, this common window being at least one exit point for the radiation directed towards the marked disc (11) and at least for the radiation reflected by the marked disc (11). 15. The angle sensor according to claim 14, further comprising an incident point. 16. A method for determining a reference signal from an analog signal, the analog signal comprising a number of marked discs and at least one reflective mark whose modulation quality differs from the marked discs. Obtained by modulation of the transmitted signal, the modulated signal being received by the receiver,
From the analog extremum of the preceding angle mark, for each angle mark and reference mark, in a method, which is fed to the evaluation unit and further digitized if necessary,
A method, characterized in that an extremum that continues this trend of extrema is determined, modified by a predetermined value and used in the evaluation unit as a threshold indicating a different reference value for the modulation. 17. For each of the angle mark and the reference mark, an extreme value corresponding to the tendency of the extreme value is determined from the analog extreme value of the extreme value of the preceding angle mark, and the extreme value is changed by a predetermined value to have different brightness. 17. Method according to claim 16, characterized in that it is used in the evaluation unit as a threshold value indicating a reference value. 18. Modulation of the electromagnetic radiation of the transmitter (41) is carried out by means of angle marks and reflection marks in the form of changes of reflected or transmitted radiation.
A method according to claim 17 wherein the analog extrema of intensity are determined and evaluated.